Rotary reversing switch



Allg 9, 1949 w. c. FURNAS ET Al.

ROTARY REVERSING SWITCH Filed Dec. 9, 19116- 2 Sheets-Sheet l INVENTORS Allg- 9, 1949- w. c. FURNAs ET Al.

ROTARY REVERSING SWITCH zvsneetssheet 2 FiledDec. 9, 1946 INVENTOR` Patented Aug. 9, 1949 ROTARY REVERSING SWITCH William C. Furnas, Batavia, and Edward L. Rocks, Aurora, Ill., assignors to Furnas Electric Company, Batavia, Ill., a. corporation oflllinois' Application December 9, 1946, Serial No. 715,012 lleClams. (Cl. Z-11) Our invention relates generally to improverotary reversing switch assemblage which isy adapted for diverse uses to control either direct or alternating current electricalv apparatus.

To provide an improved reversing switch unit in which` the fixed and movable contacts are most effectively insulated against possible short circuiting, and which may be conveniently mounted in various positions so as to meet varying conditions.

To provide a sturdy rotary switch wherein the contacts are quickly and effectively engaged and disconnected with a wiping snap actionr and which. may be operated. for a long period of time without necessitating renewal of parts.

vTo provide a simple switch assembly of the rotary reversing type. all parts of which are readily accessible for inspection, and. which may also be quickly assembledv or dismantled.

To provide an attractive rotary reversing switch which may be manufactured of durable materials and sold at moderate cost, and which is especially adapted for use in controlling the operation of various types of electric motors and other equipment To provide an improved electric switch assemblage comprising relatively few simple but stiudy parts which maybe readily associated with each other to produce a safely manipulable switch.

These and other specific objects and advan tages of the present invention will be apparent from the following' detailed description.

A clear conceptionV of the features constituting our present improvement, and of the mode of constructing and of utilizing a, typical rotary reversing switch embodying the invention, may be had by referring to the drawings accompanying and forming a part of this specification wherein like reference characters designate the same or similar parts in the various views.

Fig. 1 is a top plan view of a typical rotary reversing switch having the contacts open and upper parts removed', this` switch being adapted for either direct current, or one, two or three phase usage;

Fig. 2 is ak longitudinal partial section through the entire rotary reversing switch assemblage oi Fig. l, showing two cooperating fixed and movable contacts in closed position and also having most of the xed contacts omitted for the of clearness, and the section having been taken rather irregularly through one set of contacts on one side of the casing axis and through a corner of the casing on the opposite side of this Fig. 3 is a bottom view oi the improved switch unit of Figs. land 2;

Fig. iA is a transverse section through the sam switch assembly, taken along theV line 4-fl o Fig..2;

Fig. 5 is a combinedY bottom view and internal connection diagram showing forward and reverse positions ofthe connections at the left and right sides, beneath the bottom view, and also showing the switch in open position between the diagrams;

lFig. 6v is a side elevationof the assembled switch showing one method of mounting the same upon a panel;

Fig. 7 is another side elevation of the switch unit showing a d'ilerent mode of mounting;

Fig. 8 is a modified arrangement of movable contacts adapted to be utilized in the switch;

Fig. 9 is a further modied movable contact structure;

Fig. 10 is another modied type of movable contact assemblage; and

Fig. 11 is still another modified arrangement of the movable contacts.

While the invention has been shown and described herein as being advantageously applicable to a relatively small and compact rotary reversing switch, it is not. our desire or intention to unnecessarily restrict the scope or utility of the improved features by virtue of this limited typical embodiment.

Referring to the drawings, the typical rotary reversing switch shown therein, comprises in general. a unitary main body or casing I4 having approximately square transverse external crossu section and being provided with a hollow circular interior spanned by a fixed contact supporting Web l5 having a central bearing hub I6 and also having an annular series of six openings l1 adjacent to the casing wall; a closure cover I8 coacting with an end ofthe casing i4 and having an annular flange i9 snugly iitting the circular casing. interior, while its central portion is provided with a bearing bore 2U disposed in axial alinement with a bearing socket 2| formed in the fixed casing hub I6, the cover I8 also having therein a lobular pocket 22 adjoining the bore 29; a unitary movable contact supporting rotor 24 confined between the casing hub I6 and cover I3 and having a cylindrical projection 25 at one end journalled for rotation in the cover bore 29 and also having radial lobes 26 oscillatable within the pocket 22, while its opposite end is provided with a circular recess 21 and the center of the rotor 24 is pierced by a square hole 28; a rotor supporting shaft 29 having a square medial portion snugly fitting the hole 28 while one of its protruding ends 39 is cylindrical and ls journalled for rotation in the fixed hub socket 2l, and its opposite protruding end 3l is square and provided with a threaded socket 32; a manipulating handle 34 having a grip knob 35 and a pointer 36 radiating from opposite sides of a central hub provided with a reenforcing plate `31 and which is secured to the square shaft end 3l by means of a screw 38 coasting with the socket 32; a series of six resilient fixed contacts 39 secured to the casing web I5 by bushings 40 and each having a V-shaped contact portion 4I extending through and beyond an adjacent web opening I1; arcuate sets of rigid movable contacts 42 firmly embedded in the rotor 24 and being provided with contact notches 44 cooperable with the V-shaped rigid top portions ii of the adjacent fixed contacts 39; and two pairs of screws 45, 46 for interconnecting the casing I4 and cover I8 and for'atta'ching the switch assembly to a panel 41 or other support.

The main casing or body I4 is preferably formed of molded electrical insulation such as plastic and has the contact supporting web I formed integral with its outer wall while the central rotor supporting hub I 6 is also formed integral with the web I5; and the web I5 and hub I6 may also be reenforced by radial ribs 48 formed integral therewith and disposed between the openings I1 of the web. The closure cap or cover I8 together with its integral annular flange I9 is also preferably formed of molded electrical insulating material, and this cover I 8 maybe provided on its outer exposed surface with suitable indicia with which the handle pointer 36 is cooperable'to designate off, forward and reverse settings of the handle 34, in a well known manner. The cover I8 may also be provided with a small peripheral projection 49 adapted to coact with a similarly shaped notch formed in the adjacent end of the casing I4, in order to insure proper initial assembly of the casing and cover; and the cover flange I9 should be of suicient length to permit panels 41 of varied and considerable thickness to be inserted between the casing I4 andcover I8 as shown in Fig. 6 without openly exposing the contacts, and to also maintain safe electrical Vspacing between the contacts and the panel 41. The two diagonally opposite fastening screwsv 45 which directly unite the cover and casing, are of less length than the other two screws 46, and the latter should be long enough to project outwardly beyond the end of the casing I4 remote from the cover i8 a considerable distance as clearly indicated in Figs.

6 and 7. The protruding ends of the long screws e5 are threaded for the reception o f clamping nuts l but these threaded projecting screw ends may also be utilized to clamp the casing I4 and cover i8 to any other type of support such as another casing or housing, or the like.

The switch rotor 24 together with its bearing portion and lobes 26, are likewise preferably molded of electrical insulating plastic material 2l or the like, so as to provide a unitary structure, and the arcuate movable contacts 42 are formed of metal being rmly embedded within the rotor during the molding operation with their notched portions 44 accurately centralized relative to the rotor axis and projecting slightly from the rotor periphery, as depicted in Figs. l and 2. The integral lobes 26 of the rotor 24 are adapted to lie and oscillate within the cover pocket 22 when the parts have been properly assembled; and the portion of the rotor 24 nearest the casing web I5 is enlarged in diameter and provided with a series of indexing notches 5I located midway between the successive movable contact notches 44 and with which the resilient V-shaped portions 4I of the adjacent fixed contacts 39 are engageable when the handle 34 is in off or neutral position, see Figs. 1 and 2. These indexing notches 5I are preferably located considerable distance away from the zone of engagement of the contact portions ll and notches 44 in order to avoid destruction of the indexes by possible arcing and wearing of the contacts. The' central rotor supporting shaft 29 is preferably formed of durable metal, and should be pressed into the square central rotor hole 28, and a O-shaped Washer 52 snugly engages the shaft 29 adjacent to the cylindrical bearing portion 36 and within the recess 21 in a manner whereby the rotor body is maintained properly spaced from the supporting or bearing end of the shaft 29. It ls'to be noted that the rotor 24 is thus journalled for rotation or oscillation in two ample bearings locatedV at opposite ends of the rotor, one bearing being provided by the cover bore 29 and the other being likewise provided by the casing socket 2|.

The rotor manipulating handle 34 is again preferably formed of electrical insulating plastic or the like, except for the reenforcing bar or plate 31 which is preferably formed of metal and iirmly embedded within the handle during the molding operation, and the handle hub has a pocket therein which ls cooperable with an annular lip on the cover I8 to provide a close-fitting labyrinth seal. This plate 31 isprovided with a square opening which is snugly cooperable with the square end portion 3l of the shaft 29, and the screw 38 serves to detachably attach the handle 34 to the shaft end 3l in an obvious manner. Due to the f square formation o f the shaft end 3l, the manipulating handle 34 may be applied thereto in various positions relative to the shaft axis; and the radial rotor lobes 26 which coact with the cover pocket 22 serve to limit the extent of oscillation or swinging of the handle 34 so as to positively stopthe rotor 24 in forward and reverse positions. When the rotor 24 is positioned as shown in Figs. l, 4 and 5, the movable contact projections 42 are disposed between the V-shaped rigid z top portions 4I of the adjacent fixed contacts 39,

and the switch is then in neutral or olf position; but when the handle 34 is swung into either forward or reverse position as determined by the lobes 26, then the movable conta-ct projection i. notches 4d will be snugly engaged by the adjacent V-shaped portions 4I of the fixed contacts 39 as clearly indicated in Fig. 2 and in the diagrams of l Fig. 5. The fixed contacts S9 which are fastened to the casing web I5 by means of the threaded bushings 4B, are adapted to be connected to various types of electrical equipment and apparatus by means of conductor atta-ching screws 54, and the conductors may be conveniently introduced into, the switch `casing through the open end thereof remote from the closure cover I8.

arranco them to function effectively even in cases where f panels 41 of diiierent thickness are inserted between the main casing I4 and cover It; and the resilient portions of the stationary contacts 39 which connect the V-shaped portions 4| with the bushings 4l), are of suriicient length and resiliency to maintain the contact portions 6| approximately parallel and to constantly resiliently urge these portions against the rotor 24 at all times with considerable pressure.

While the arcuate movable contacts 42 shown l in Figs. 1 to 5 inclusive, are especially adapted for use in ordinary electrical systems in order to obtain forward and reverse movement of a motor or the like, various other movable contact arrangements for special systems are also made possible gy, nxed contacts secured to said web entirely within with our improved switch assembly, by merely substituting rotors 2d having other formations of movable contacts embedded therein, as shown in Figs. 8, 9, and 1l. In Fig. 8, the movable contact assembly consists of three identical arcu.- ate movable contacts E2 each having two contact notches 44; while in Fig. 9 a single arcuate movable contact l2 having two diametrically opposite contact notches M is illustrated. In Fig. 10 the movable contact assemblage comprises two identical movable contacts 82 disposed diametrically opposite each other and each provided with two contact notches 44; whereas in Fig. 11 two movable contacts 32 of different length are utilized, one of these having only two contact notches 44 while the other has three such notches. These various movable contacts 42, 52, i2, 82, QZ may be employed in standard rotors 24 which are cooperable with all other elements of the improved switch assemblage previously described, thus providing extreme flexibility in adaptation and use of the improved unit in connection with both standard and special alternating and direct current electrical systems.

The normal use of the improved switch should be clearly apparent to those skilled in the art, from the foregoing description of its specific construction, and it should be noted that the present invention provides an improved rotary reversing switch which is in fact simple in construction, eiiicient in operation, and adapted for diverse uses to control various types of electrical equipment and apparatus. The improved switch assembly while being exceedingly compact and durable, has all parts thereof effectively insulated against short circuiting and possible danger, and the various insulating elements may be readily molded of attractive plastic insulating material to produce a highly aesthetic but practical assemblage. The various parts of the mechanism are also sturdily constructed with ample supporting bearings for the rotor, but the parts may be quickly and conveniently assembled or dismantled and mounted upon panels or other supports in diverse positions so as to meet varying conditions. The improved :formation of the handle 3d with an annular pocket snugly cooperating with an annular lip on the adjacent cover i8, protects the internal mechanism against possible Oil or water seepage, by providing a labyrinth packing around the rotor supporting shaft 29, and the typical switch unit shown is adapted to be utilized in either direct current, or alternating current single or multiple phase electric circuits. All parts of the switch unit are also readily accessible for inspection and installation, and may be manufactured at moderate cost; and the improved rotary reversing switch has proven highly satisfactory and successiul in actual use.

It should be understood that it is not desired to limit this invention to the exact details of construction or to the precise mode of use, herein shown and described, for various modications within the scope of the appended claims may occur to persons skilled in the art; and it is further contemplated that various specific descriptive terms used herein be given the broadest possible interpretation consistent with the disclosure.

We claim:

l.. An electric switch comprising, a tubular casing formed of insulating material and being divided by an integral internal web into two segregated end chambers, an annular series of one od said chambers and projecting through restricted openings in the web into the other chamber, a closure cover for said other chamber formed of insulating material and having an integral tubular flange slip-ntting the interior of said casing, and a rotor formed of insulating material and being jcurnalled for rotation in said cover while conined within said other chamber, said rotor having movable contacts embedded therein and cooperable with said xed contacts within said cover flange and also having indexing notches cooperable with said iixed contacts remote from said movable contacts.

2. An electric switch comprising, a casing, an annular series oi resilient iixed contacts mounted within said casing and each having a V-shaped contact portion, a rotor mounted within said casing and having an annular series of rigid inovable contacts each provided with a similarly V-shaped notch foirmed .for extensive surface engagement with only one of said V-shaped xed contact portions during establishment of each successive electric circuit, and means for effecting step-by-step rotation of said rotor relative to said casing.

3. An electric switch comprising, a casing, an annular series of resilient fixed contacts mounted within said casing and each having a V-shaped contact portion, a rotor mounted within said casing and having :an annular series of rigid movable contacts each provided with a central similarly V-shaped notch and arcuate contact portions on op-posite sides of each notch, said arcuate movable contact portions being engageable with the V-shaped portions of said Iixed contacts before the latter enter into extensive surface engagement with the V-shaped notches, and means for eiecting step-by-step rotation of said rotor relative to said casing.

4. An electric switch comprising, a casing, an annular series of resilient iixed contacts mounted within said casing and each having a V-shaped contact portion, a rotor mounted within said casing and having an annular series of rigid movable contacts each provided with a similarly V-shaped notch engageable with only one of said rl-shaped xed contact portions during establ-ishment of each successive electric circuit, said rotor also having thereon an annular series of insulated indexing V-notches spaced laterally away from said movable contacts a considerable 8 UNITED STATES PATENTS" distance and cooperable with said xed contacts Number Name Date when inactive, and means for effecting stepby 1 919 949 Kempton July 25 1933 step rotation of said rotor relative to said easing. 2015874 Schoeld Oct. l 1935 5 2,163,919 Siegel June 27, 1939 gnv'' FURNAS- 2,201,881 Bryant et a1. May 21, 1940 RUCKS- 2,210,842 schenenger Aug.6,194o

FOREIGN PATENTS Country Date Great Britain May 31, 1938 REFERENCES CITED The follow-ing referenices are of record in the 10 Number file of this patent: 486,516 

